1. Field of the Invention
The present invention relates generally to a mat employed, for example, as building interior material and components of household commodities, and more particularly, to a mat having absorbs moisture and deodorizes, as well as, to a process for producing the same.
2. Description of the Related Art
Generally, rooms in concrete buildings are highly airtight. The high room airtightness readily induces dew condensation in the room and results in insufficient ventilation of the room. Humidity in the room adversely affects the interior wall and furniture. In order to solve these problems, mats containing moisture absorbents such as silica gel and/or deodorants such as activated carbon are utilized as building interior materials such as for flooring (wall-to-wall) carpets and wall lining materials. Three conventional techniques given below are known as silica gel-containing wall lining materials.
A wall lining material to be formed according to a first conventional technique is composed of a plywood core material, granular silica gel and a sheet. The core material contains a plurality of holes opening on one side thereof. These holes are filled with silica gel, and the openings of the holes are covered with an air-permeable sheet such as a nonwoven fabric. The thus formed wall lining material is applied to the concrete wall surfaces such that the sheet is exposed to the room. The silica gel contained in the holes absorbs moisture in the room through the sheet to prevent dew condensation in the room from occurring.
The wall lining material formed according to a second conventional technique is composed of two sheets of fabric having air permeability and granular silica gel. These two sheets are sewn up together by threads with the silica gel being interposed therebetween. The sheets are sewn up together such that a plurality of pockets are defined therebetween and such that the silica gel is contained in each pocket. Like the first conventional technique, this wall lining material is applied to the concrete wall surfaces such that one sheet is exposed to the room. Thus, the silica gel in the pockets absorbs the moisture in the room through the sheet.
The wall lining material formed according to a third conventional technique is composed of two mat bodies made of air-permeable nonwoven fabric and granular silica gel. The two mat bodies are adhered to each other by an adhesive with a silica gel layer being sandwiched between them. Like the first and second conventional techniques described above, this wall lining material is applied to the concrete wall surfaces such that one mat body is exposed to the room. Thus, the silica gel sandwiched between two mat bodies absorbs the moisture in the room through the mat body.
However, the wall lining materials according to the conventional techniques described above involve the following problems. In the first conventional technique, the silica gel having moisture absorbing function is present only in some holes defined on one side of the core material. The total area of the holes occupying the entire wall lining material is very small, so that the moisture absorbing function of silica gel cannot be fully employed. In order to increase the moisture absorbing area, the number of holes defined on one side of the core material or the area of each hole can be increased. However, this reduces in the strength of the core material. Accordingly, there is a limitation in increasing the number of holes or the area of each hole. Further, the portion of silica gel present at the bottom of each hole cannot fully function to absorb moisture compared with that portion adjacent to the opening of the hole.
In the second conventional technique, if the sheet is applied to the concrete wall surface, the silica gel contained in each pocket gathers at the bottom of the pocket to form a lump, which results in an irregular wall surface and deteriorates the appearance of the wall surface. Further, in the second conventional technique, the moisture absorbing area of the wall lining material is reduced if the silica gel gathers at the bottom of each pocket.
In the third conventional technique, since the mat bodies are adhered to each other by an adhesive, the adhesive is applied on the surface of the silica gel. This adhesive greatly reduces moisture absorbing function of the silica gel. Silica gel has a multiplicity of fine holes on its surface, which absorb moisture by the capillary phenomenon. However, the adhesive blocks these fine holes present on the surface of silica gel.